.\" -*- nroff -*-
.\" Copyright 2010 Cisco Systems, Inc.  All rights reserved.
.\" Copyright 2006-2008 Sun Microsystems, Inc.
.\" Copyright (c) 1996 Thinking Machines Corporation
.\" $COPYRIGHT$
.TH MPI_Errhandler_create 3 "Jun 10, 2020" "4.0.4" "Open MPI"
.SH NAME
\fBMPI_Errhandler_create \fP \- Creates an MPI-style error handler -- use of this routine is deprecated.

.SH SYNTAX
.ft R
.SH C Syntax
.nf
#include <mpi.h>
int MPI_Errhandler_create(MPI_Handler_function *\fIfunction\fP,
	MPI_Errhandler *\fIerrhandler\fP)

.fi
.SH INPUT PARAMETER
.ft R
.TP 1i
function
User-defined error handling procedure.

.SH OUTPUT PARAMETERS
.ft R
.TP 1i
errhandler
MPI error handler (handle).
.ft R
.TP 1i
IERROR
Fortran only: Error status (integer).

.SH DESCRIPTION
.ft R
Note that use of this routine is \fIdeprecated\fP as of MPI-2. Please use MPI_Comm_create_errhandler instead.
.sp
This deprecated routine is not available in C++.
.sp
Registers the user routine function for use as an MPI exception handler. Returns in errhandler a handle to the registered exception handler.
.sp
In the C language, the user routine should be a C function of type MPI_Handler_function, which is defined as
.sp
.nf
    typedef void (MPI_Handler_function)(MPI_Comm *, int *, \&...);
.fi
.sp
The first argument is the communicator in use. The second is the error code
to be returned by the MPI routine that raised the error. If the routine would have returned MPI_ERR_IN_STATUS, it is the error code returned in the status for the request that caused the error handler to be invoked. The remaining arguments are stdargs arguments whose number and meaning is implementation-dependent. An implementation should clearly document these arguments. Addresses are used so that the handler may be written in Fortran.

.SH NOTE
.ft R
The MPI-1 Standard states that an implementation may make the output value (errhandler) simply the address of the function. However, the action of MPI_Errhandler_ free makes this impossible, since it is required to set the value of the argument to MPI_ERRHANDLER_NULL. In addition, the actual error handler must remain until all communicators that use it are freed.

.SH ERRORS
Almost all MPI routines return an error value; C routines as the value of the function and Fortran routines in the last argument. C++ functions do not return errors. If the default error handler is set to MPI::ERRORS_THROW_EXCEPTIONS, then on error the C++ exception mechanism will be used to throw an MPI::Exception object.
.sp
Before the error value is returned, the current MPI error handler is
called. By default, this error handler aborts the MPI job, except for I/O function errors. The error handler may be changed with MPI_Comm_set_errhandler; the predefined error handler MPI_ERRORS_RETURN may be used to cause error values to be returned. Note that MPI does not guarantee that an MPI program can continue past an error.

.SH SEE ALSO
.br
MPI_Comm_create_errhandler
.br
MPI_Comm_get_errhandler
.br
MPI_Comm_set_errhandler



